Privacy

This site is run by Useful Build, a studio operated by Karko AI Inc., 1207 Delaware Ave #412, Wilmington, DE 19806, USA. We collect very little, and this page says exactly what.

What we collect

Analytics. We use PostHog US Cloud to understand page views, booking and email clicks, browser and device information, approximate country, Web Vitals and JavaScript errors. We also use privacy-masked session replay to see where the site is confusing. Inputs are masked, client IP addresses are discarded and we don't create account identities or advertising profiles.

Headline experiment. PostHog stores an anonymous browser identifier and the assigned headline in browser storage so repeat visits can stay consistent. Preview links are excluded from analytics. Booking-form answers remain with Cal.com and are not sent to PostHog.

Email and booking. When you write to hello@usefulbuild.com or book a call, we keep that correspondence so we can reply and work with you.

What we don't do

We don't sell your data. We don't run ad networks or cross-site tracking. We don't train AI models on anything you send us.

Hosting

The site is served by Cloudflare, which processes technical request data (like IP addresses) to deliver the site and protect it from abuse, acting as our infrastructure provider.

How long we keep things

PostHog retains analytics events for seven years and session recordings for 30 days in the current project. PostHog provides a Data Processing Addendum and is certified under the EU-US Data Privacy Framework. Email correspondence is kept while we're in contact or as the law requires.

Analytics choice

Useful Build primarily markets to businesses in the United States and Canada and launches this analytics setup without a consent banner. We will review this approach if our market focus, traffic mix or legal obligations change. You can block analytics with a tracker-blocking extension and the site will continue to work.

Your rights

Depending on where you live (including under the GDPR, UK GDPR and CCPA), you can ask us what we hold about you, ask us to correct it or delete it, and object to how it's used. Email hello@usefulbuild.com and we'll sort it out.

Children

This site is for businesses and isn't directed at children. We don't knowingly collect data from anyone under 16.

Changes

If this policy changes, the new version appears here with a new date.

Contact

Karko AI Inc., 1207 Delaware Ave #412, Wilmington, DE 19806, USA · hello@usefulbuild.com

Effective July 16, 2026.